A high-profile employment law firm has been hired to probe allegations of inappropriate behaviour within the Prime Minister's Office.
Rubin Thomlinson LLP is the independent third party handling the investigation into Claude-Éric Gagné, the deputy director of operations within the PMO.
Janice Rubin, who led the independent investigation of the Canadian Broadcasting Corporation following the dismissal of radio host Jian Ghomeshi, is a partner at the firm.
However, a spokeswoman for the PMO refused to say if Rubin is directly involved in this investigation.
Trudeau's director of communications, Kate Purchase, said in a statement that an investigation was "immediately triggered with the assistance of an independent investigator and the individual in question went on leave, pending the outcome."
The PMO refused to identify the staffer involved or provide any details of the allegations, but a source previously confirmed to CBC News that they are against Gagné and involve allegations of inappropriate behaviour.
TVA, a French-language television network, first revealed the investigation into Gagné and that he has been on leave since early November.
In a statement in French to Radio-Canada, Gagné said he is on leave because of an independent investigation into "allegations which were brought to the attention of my employer."
Gagné said he takes the situation seriously and has offered his "full and complete collaboration to the investigator," who he said has given him the opportunity to "explain my version of the facts in light of these allegations which I dispute."
Rubin is well known in Toronto's legal community, and garnered headlines for her investigation into workplace culture at the CBC.
She found CBC mishandled managing Ghomeshi, amid reports of abusive behaviour in the workplace